Add test flags feature to perf runner.

tools/unittests/run_perf_test.py

 #!/usr/bin/env python
 # Copyright 2014 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from collections import namedtuple
 import coverage
 import json
 from mock import DEFAULT
 from mock import MagicMock
@@ skipping 161 matching lines @@
     self._WriteTestInput(V8_JSON)
     self._MockCommand(["."], ["x\nRichards: 1.234\nDeltaBlue: 10657567\ny\n"])
     self.assertEquals(0, self._CallMain())
     self._VerifyResults("test", "score", [
       {"name": "Richards", "results": ["1.234"], "stddev": ""},
       {"name": "DeltaBlue", "results": ["10657567"], "stddev": ""},
     ])
     self._VerifyErrors([])
     self._VerifyMock(path.join("out", "x64.release", "d7"), "--flag", "run.js")
 
+  def testOneRunWithTestFlags(self):
+    test_input = dict(V8_JSON)
+    test_input["test_flags"] = ["2", "test_name"]
+    self._WriteTestInput(test_input)
+    self._MockCommand(["."], ["Richards: 1.234\nDeltaBlue: 10657567"])
+    self.assertEquals(0, self._CallMain())
+    self._VerifyResults("test", "score", [
+      {"name": "Richards", "results": ["1.234"], "stddev": ""},
+      {"name": "DeltaBlue", "results": ["10657567"], "stddev": ""},
+    ])
+    self._VerifyErrors([])
+    self._VerifyMock(path.join("out", "x64.release", "d7"), "--flag", "run.js",
+                     "--", "2", "test_name")
+
   def testTwoRuns_Units_SuiteName(self):
     test_input = dict(V8_JSON)
     test_input["run_count"] = 2
     test_input["name"] = "v8"
     test_input["units"] = "ms"
     self._WriteTestInput(test_input)
     self._MockCommand([".", "."],
                       ["Richards: 100\nDeltaBlue: 200\n",
                        "Richards: 50\nDeltaBlue: 300\n"])
     self.assertEquals(0, self._CallMain())
@@ skipping 180 matching lines @@
     self._VerifyResults("test", "score", [
       {"name": "Richards", "results": [], "stddev": ""},
       {"name": "DeltaBlue", "results": [], "stddev": ""},
     ])
     self._VerifyErrors([
       "Regexp \"^Richards: (.+)$\" didn't match for test Richards.",
       "Regexp \"^DeltaBlue: (.+)$\" didn't match for test DeltaBlue.",
     ])
     self._VerifyMock(
         path.join("out", "x64.release", "d7"), "--flag", "run.js", timeout=70)